Incidence of hypercalcemia and malignant neoplasm.

Hypercalcemia often complicates the course of patients with malignant neoplasms. Since this metabolic derangement is potentially lethal, knowledge of the expected relative incidence of hypercalcemia in various malignant neoplasms is of importance. The incidence of hypercalcemia and malignant neoplasm at the Clinical Center, National Institutes of Health, Bethesda, Md, was reviewed. Of 17,706 admissions (multiple admissions counted once), the overall incidence of hypercalcemia for all disorders was 5.0%; of these, 38.0% (338 patients) had associated neoplasms (99.4% malignant). Primary hyperparathyroidism represented 19.6% of those admitted with hypercalcemia, and nonneoplastic disorders represented 10.7%. Of the 338 patients with hypercalcemia associated with neoplasia, 44.1% had hematologic and 41.4% had solid neoplasms. The relative incidences of hypercalcemia and neoplasia are reported for each of the solid and hematologic neoplasias evaluated.